Category Archives: Linq

LINQ: The overloaded Contains Operator

A LINQ Tutorial As part of my continuing (and occasional) series of mini-tutorials on LINQ this posting will consider the overloaded Contains operator. This operator allows you to check whether a list contains a given value, as illustrated in the … Continue reading

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Managing Resources with Reactive Extensions

Reactive Extensions While Reactive Extensions will clean up after itself, it is still your responsibility to manage limited resources, and to dispose of  any unmanaged resources. You can, however, use a variant on the using statement with Observables.

Posted in Data, Linq, Mini-Tutorial, Reactive | Tagged | 6 Comments

Reactive Extensions–FromAsync

Reactive Programming I’ve been struggling with getting my head around the exact relationship between Rx’s approach to asynchronous programming and the traditional Begin/End pattern common in .NET programming. With the help of Paul Betts I created a side by side … Continue reading

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LINQ Deferred Execution–Oops!

A LINQ Tutorial Deferred execution can be a lifesaver with LINQ but it can have a downside as well. In this example we set up a LINQ query and then iterate through the results twice. The output may not be … Continue reading

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Best Practices For Local Databases

Mango From Scratch I’ve recently written two posts about coding for SQL CE in Mango (the next release of Windows Phone).  Sean McKenna, who knows more about this than anyone walking the planet, dropped me an email to remind me … Continue reading

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Coming In Mango–Local DB Part 2: Relationships

On May 10 I posted about the upcoming addition of SQL Server Compact Edition (CE) in Windows Phone Mango.  At that time, I showed how to create the DataContext object and how to store and retrieve “flat” data. In this … Continue reading

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Coming in Mango–Sql Server CE

Mango From Scratch With the forthcoming Mango release of Windows Phone (tools to be released this month) you can store structured data in a Sql Server Compact Edition (CE) database file in isolated storage (called a local database). You don’t … Continue reading

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LinqPad, Linq Queries and IEnumerable

This posting is part of an on-going series on LINQ – a critical tool for both Windows Phone and Silverlight Programmers. I recently discovered LinqPad, a free utility developed by Joseph Albahari that supports Linq to Objects, Linq to SQL, … Continue reading

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Linq: SelectMany

Windows Phone From Scratch #47 A LINQ Tutorial SelectMany is a crucial operator in both LINQ and in Reactive Extensions.  It may be easier to see what it does by focusing on LINQ, as most of us are more familiar … Continue reading

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Deferred Execution in LINQ

A LINQ Tutorial As part of my on-going exploration of technologies related to programming Silverlight and Windows Phone, I’ve been exploring LINQ in some detail. Today, I’d like to take a look at how LINQ queries are executed; specifically focusing … Continue reading

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Yet Another Podcast #27–Paul Betts

Paul Betts works in Office Labs at Microsoft and is the creator of Reactive UI – an MVVM framework based on Reactive Extensions. Reactive UI Paul’s Blog NuGet Page Reactive UI Download and Source Listen| Return to Yet Another Podcast … Continue reading

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Reactive Drag and Drop Part 2

Reactive Programming, Posting # 7 In Part 1 of this 2 part posting we looked at capturing the mouse movements.  The key code in Part 1 was, var q = from start in mousedown from pos in mousemove.StartWith( start ) … Continue reading

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